Bore sight



Patented Sept. s, 1942 lleruun l. Klfllllll, United Stute: Anny, Wulsillgflm, D. 0., uul Dolldu L. hl'khlll'lt, 8llinlhe l, Mus.

Abpllcaflon Inne 2, 1941, Serial N0. 396,286

3 China. (GI. 33-46) (Grsnted umher the ad; o! Mach 3, 1883, a: &lllelldd April 30, 1928; 370 O. G. 757) The invention descrlbed herein may be manufactured und used by or for the Government. for governmental purposes, without I:he payment to us of any royalty thereon.

'I'his invention rela.tes I;o a telescopic bore sight.

A principal object cf the invention is to provide a simple telescope mounting adapted for use in acqurately mounting a telescope in the chamber of a. gun with its optical axis coinciding with the axis 015 the bore of the gun.

A further object o1 the invention is to provide a bore sight mounting adapted to be positioned in the chamber of any gun cf the same caliber in such manner as to accurately position the a.xis of the bore sight in coincident relationwith the axis of the bore of the gun.

The specific nature of the invention as well as other objects and advantages thereof will clearly appear from a. description of a preferred embodiment as shown in the accompanying dra.wing in which:

Fig. 1 is a longitudinal sectional view through the breech end portion of a gun showing the bore sight of this invention, also in longitudinal section, mounted in the chamber thereof.

Fig. 2 is a sectional view taken upon the line 22 015 Fig. 1.

Referring now to the drawing, and more part-icularly to Fig. 1, there is shown the breech end portion of a gun III provided with a conventional cartrigige chamber II of generally truncated cqnica1 form. The bore sight of this invention, generally indicated at I2, is mounted in the chamber II with its axis I3 in coincident relation to the axis II of the bore of the gun by means 015 a tubular bore sight mounting member I5 provided with a. concentrically disposed outwardly protruding flange or other suitable support IG adjacent its forward end adapted to engage a. complementary section of the chamber I I coucentrically of the a.xis thereof. The rear end portion of the mounting member I5 is of reduced section as indicated a.t I'I to form a shoulder I 8 intermediate its ends.

A tubular element I9 is mounted upon the reduced section I'I of the mounting member I5 for adjustable sliding movement coaxially of the member I5 between a forward position of abutment with the shoulder I8 a.nd any desired position rearwardly of the forward position. The element I9 is formed with a. concentric outwardly protruding flange or other suitable support 20 of somewhat langer diameter than the flange Ili for engaging the adjacent portion of chamber II in a manner to support member I5 coaxially of the axis II of the bore und chamber oi the gun. Conveniently the flange 20 is located intermediate the ends of the tubular element I9 a.nd the la.tter ma.y be provided with a suitable finger piece adjacent its rear end to facilitate adjustment of the element for adaptlng the flange 20 to concentrically engage the chamber wall when used in various guns having chambers II of different degrees of conicity.

The telescopic bore sight I2 coxnprises the usual objective 2I, telescope tube 22, adjustable eyepiece 23 and reticle 24 and is arranged with its objective end portion disposed within the mounting member I5 in a. supported position with its axis I3 disposed coaxially oi the member I5. T0 facilitate positioning of the bore sight in proper position within the member I5 the tube 22 thereof may be formed with a flange 25 or other suitable stop element to engage the unter endet the member I5.

Having now described a present preferred embodiment 015 the lnvention, we c1aim:

1. In a. bore sight for a, gun having a generally truncated conical chamber, a tubular sight mounting member adapted to mount a. bore sight on the interior thereof formed to provide a surface adapted to concentribally engage a. complementary wall section of said chamber adjacent the small end 0fhe latter, an element mounted upon the mounting member for coaxial sliding movement thereon, said element being formed with concentric means for engaging a complementary wall section of said chamber spaced from gaidfirst named complementary wall section; whereby said sight may be arranged in the chamber with its axis in coincident relation to the axis of the chamber.

2. In a bore sight for a gun having a. generallv trunc'ated conical chamber, a. tubular sight mounting member, an outwardly protruding cancentric support formed on said member adjacent its forward end adapted to engage a complementary wall section of said chamber, a, tubular element mounted upon the rear endportion of the member for coaxial sliding movement thereon, said element being formed with an outwardly protruding concentric support surface for engaging a complementary wall section of said chamber rearwardly spaced from said first named complementary wa1l section; whereby said sight may be arranged in the chamber with its axis in coincident relation to the ax1's of the chamber.

3. In a bore sight for a gun having a generally truncated conical chamber, a tubular sight mounting member provided with a, rear end portion o! outside reduced section, said mountii1g mexnber belng provlded with an outwardly protruding concentric flange adjacent its forward end adapted to engage a. complementary wall diameter tha.n seid flange on the mounting memher for engaginga complementary wall sectlon of said chamber rea.rwardly spaced fro1 n said flrst named compl ementary wall section; where'- by said sight may be arranged in the chamber with its axis in coincident relation to the axis' of the cha.mber.

.HERMAN P. KAUFMAN. DOUGLAS L. PARKHURST. 

